Answer:
group I: alkali metals
group II (beryllium to radium): alkaline earth metals
group II (scandium to zinc , yttrium to cadmium, lanthanoid series to mercury, actinoid series to copernicium): transition metals
group VII (fluorine to astatine): halogens
group VIII: (helium to radon): noble gases
Explanation:
Answer:
At standard room temperature, ![[{\rm OH^{-}] \approx 2.5 \times 10^{-7}\; \rm M](https://tex.z-dn.net/?f=%5B%7B%5Crm%20OH%5E%7B-%7D%5D%20%5Capprox%202.5%20%5Ctimes%2010%5E%7B-7%7D%5C%3B%20%5Crm%20M)
when ![[{\rm H^{+}] = 4.0 \times 10^{-8}\; \rm M](https://tex.z-dn.net/?f=%5B%7B%5Crm%20H%5E%7B%2B%7D%5D%20%3D%204.0%20%5Ctimes%2010%5E%7B-8%7D%5C%3B%20%5Crm%20M)
.
Explanation:
The following equilibrium goes on in water:
.
The forward reaction is known as the self-ionization of water. The ionization constant of water, 
, gives the equilibrium position of this reaction:
![K_{\rm w} = [{\rm H^{+}] \cdot [{\rm OH^{-}}]](https://tex.z-dn.net/?f=K_%7B%5Crm%20w%7D%20%3D%20%5B%7B%5Crm%20H%5E%7B%2B%7D%5D%20%5Ccdot%20%5B%7B%5Crm%20OH%5E%7B-%7D%7D%5D)
.
At standard room temperature (
), 
. Also, ![[{\rm H^{+}}] = 4.0 \times 10^{-8}\; \rm mol \cdot L^{-1}](https://tex.z-dn.net/?f=%5B%7B%5Crm%20H%5E%7B%2B%7D%7D%5D%20%3D%204.0%20%5Ctimes%2010%5E%7B-8%7D%5C%3B%20%5Crm%20mol%20%5Ccdot%20L%5E%7B-1%7D)
. Substitute both values into the equation and solve for ![[{\rm OH^{-}}]](https://tex.z-dn.net/?f=%5B%7B%5Crm%20OH%5E%7B-%7D%7D%5D)
.
![\begin{aligned} {[}{\rm OH^{-}}{]} &= \frac{K_{\rm w}}{[{\rm H^{+}}]} \\ &\approx \frac{10^{-14}}{4.0 \times 10^{-8}} = 2.5 \times 10^{-7}\end{aligned}](https://tex.z-dn.net/?f=%5Cbegin%7Baligned%7D%20%7B%5B%7D%7B%5Crm%20OH%5E%7B-%7D%7D%7B%5D%7D%20%26%3D%20%5Cfrac%7BK_%7B%5Crm%20w%7D%7D%7B%5B%7B%5Crm%20H%5E%7B%2B%7D%7D%5D%7D%20%5C%5C%20%26%5Capprox%20%5Cfrac%7B10%5E%7B-14%7D%7D%7B4.0%20%5Ctimes%2010%5E%7B-8%7D%7D%20%3D%202.5%20%5Ctimes%2010%5E%7B-7%7D%5Cend%7Baligned%7D)
.
In other words, in an aqueous solution at standard room temperature, when .
Answer:
D: A white blood cell produces antibodies.
Explanation:
Intercellular communication is defined as the process of communication that occurs between the two cells of the same organism.
Now, these two cells relate which each other when a signal reception receives a single molecule at a distance that could be short or long which in turn produces a cellular response.
Thus, looking at the options, the correct answer is Option D.
Electrical engineers are the scientists that study the production of electricity more efficient.
<h3>
Which type of scientist would study how electricity could be produced more efficiently?</h3>
Electrical engineers are the type of scientist that would most likely study how electricity could be produced more efficiently because they produced new technologies which are cost efficient as well as produce high amount of electricity.
So we can conclude that electrical engineers are the scientists that study the production of electricity more efficient.
Learn more about electricity here: brainly.com/question/776932
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